1 /* 2 * Copyright (c) 1999, 2017, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 // no precompiled headers 26 #include "asm/macroAssembler.hpp" 27 #include "classfile/classLoader.hpp" 28 #include "classfile/systemDictionary.hpp" 29 #include "classfile/vmSymbols.hpp" 30 #include "code/codeCache.hpp" 31 #include "code/icBuffer.hpp" 32 #include "code/vtableStubs.hpp" 33 #include "interpreter/interpreter.hpp" 34 #include "jvm_solaris.h" 35 #include "memory/allocation.inline.hpp" 36 #include "os_share_solaris.hpp" 37 #include "prims/jniFastGetField.hpp" 38 #include "prims/jvm.h" 39 #include "prims/jvm_misc.hpp" 40 #include "runtime/arguments.hpp" 41 #include "runtime/atomic.hpp" 42 #include "runtime/extendedPC.hpp" 43 #include "runtime/frame.inline.hpp" 44 #include "runtime/interfaceSupport.hpp" 45 #include "runtime/java.hpp" 46 #include "runtime/javaCalls.hpp" 47 #include "runtime/mutexLocker.hpp" 48 #include "runtime/osThread.hpp" 49 #include "runtime/sharedRuntime.hpp" 50 #include "runtime/stubRoutines.hpp" 51 #include "runtime/thread.inline.hpp" 52 #include "runtime/timer.hpp" 53 #include "utilities/align.hpp" 54 #include "utilities/events.hpp" 55 #include "utilities/vmError.hpp" 56 57 // put OS-includes here 58 # include <sys/types.h> 59 # include <sys/mman.h> 60 # include <pthread.h> 61 # include <signal.h> 62 # include <setjmp.h> 63 # include <errno.h> 64 # include <dlfcn.h> 65 # include <stdio.h> 66 # include <unistd.h> 67 # include <sys/resource.h> 68 # include <thread.h> 69 # include <sys/stat.h> 70 # include <sys/time.h> 71 # include <sys/filio.h> 72 # include <sys/utsname.h> 73 # include <sys/systeminfo.h> 74 # include <sys/socket.h> 75 # include <sys/trap.h> 76 # include <sys/lwp.h> 77 # include <poll.h> 78 # include <sys/lwp.h> 79 # include <procfs.h> // see comment in <sys/procfs.h> 80 81 #ifndef AMD64 82 // QQQ seems useless at this point 83 # define _STRUCTURED_PROC 1 // this gets us the new structured proc interfaces of 5.6 & later 84 #endif // AMD64 85 # include <sys/procfs.h> // see comment in <sys/procfs.h> 86 87 88 #define MAX_PATH (2 * K) 89 90 // Minimum usable stack sizes required to get to user code. Space for 91 // HotSpot guard pages is added later. 92 #ifdef _LP64 93 // The adlc generated method 'State::MachNodeGenerator(int)' used by the C2 compiler 94 // threads requires a large stack with the Solaris Studio C++ compiler version 5.13 95 // and product VM builds (debug builds require significantly less stack space). 96 size_t os::Posix::_compiler_thread_min_stack_allowed = 325 * K; 97 size_t os::Posix::_java_thread_min_stack_allowed = 48 * K; 98 size_t os::Posix::_vm_internal_thread_min_stack_allowed = 224 * K; 99 #else 100 size_t os::Posix::_compiler_thread_min_stack_allowed = 32 * K; 101 size_t os::Posix::_java_thread_min_stack_allowed = 32 * K; 102 size_t os::Posix::_vm_internal_thread_min_stack_allowed = 64 * K; 103 #endif // _LP64 104 105 #ifdef AMD64 106 #define REG_SP REG_RSP 107 #define REG_PC REG_RIP 108 #define REG_FP REG_RBP 109 #else 110 #define REG_SP UESP 111 #define REG_PC EIP 112 #define REG_FP EBP 113 // 4900493 counter to prevent runaway LDTR refresh attempt 114 115 static volatile int ldtr_refresh = 0; 116 // the libthread instruction that faults because of the stale LDTR 117 118 static const unsigned char movlfs[] = { 0x8e, 0xe0 // movl %eax,%fs 119 }; 120 #endif // AMD64 121 122 char* os::non_memory_address_word() { 123 // Must never look like an address returned by reserve_memory, 124 // even in its subfields (as defined by the CPU immediate fields, 125 // if the CPU splits constants across multiple instructions). 126 return (char*) -1; 127 } 128 129 // 130 // Validate a ucontext retrieved from walking a uc_link of a ucontext. 131 // There are issues with libthread giving out uc_links for different threads 132 // on the same uc_link chain and bad or circular links. 133 // 134 bool os::Solaris::valid_ucontext(Thread* thread, const ucontext_t* valid, const ucontext_t* suspect) { 135 if (valid >= suspect || 136 valid->uc_stack.ss_flags != suspect->uc_stack.ss_flags || 137 valid->uc_stack.ss_sp != suspect->uc_stack.ss_sp || 138 valid->uc_stack.ss_size != suspect->uc_stack.ss_size) { 139 DEBUG_ONLY(tty->print_cr("valid_ucontext: failed test 1");) 140 return false; 141 } 142 143 if (thread->is_Java_thread()) { 144 if (!valid_stack_address(thread, (address)suspect)) { 145 DEBUG_ONLY(tty->print_cr("valid_ucontext: uc_link not in thread stack");) 146 return false; 147 } 148 if (!valid_stack_address(thread, (address) suspect->uc_mcontext.gregs[REG_SP])) { 149 DEBUG_ONLY(tty->print_cr("valid_ucontext: stackpointer not in thread stack");) 150 return false; 151 } 152 } 153 return true; 154 } 155 156 // We will only follow one level of uc_link since there are libthread 157 // issues with ucontext linking and it is better to be safe and just 158 // let caller retry later. 159 const ucontext_t* os::Solaris::get_valid_uc_in_signal_handler(Thread *thread, 160 const ucontext_t *uc) { 161 162 const ucontext_t *retuc = NULL; 163 164 if (uc != NULL) { 165 if (uc->uc_link == NULL) { 166 // cannot validate without uc_link so accept current ucontext 167 retuc = uc; 168 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) { 169 // first ucontext is valid so try the next one 170 uc = uc->uc_link; 171 if (uc->uc_link == NULL) { 172 // cannot validate without uc_link so accept current ucontext 173 retuc = uc; 174 } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) { 175 // the ucontext one level down is also valid so return it 176 retuc = uc; 177 } 178 } 179 } 180 return retuc; 181 } 182 183 // Assumes ucontext is valid 184 ExtendedPC os::Solaris::ucontext_get_ExtendedPC(const ucontext_t *uc) { 185 return ExtendedPC((address)uc->uc_mcontext.gregs[REG_PC]); 186 } 187 188 void os::Solaris::ucontext_set_pc(ucontext_t* uc, address pc) { 189 uc->uc_mcontext.gregs [REG_PC] = (greg_t) pc; 190 } 191 192 // Assumes ucontext is valid 193 intptr_t* os::Solaris::ucontext_get_sp(const ucontext_t *uc) { 194 return (intptr_t*)uc->uc_mcontext.gregs[REG_SP]; 195 } 196 197 // Assumes ucontext is valid 198 intptr_t* os::Solaris::ucontext_get_fp(const ucontext_t *uc) { 199 return (intptr_t*)uc->uc_mcontext.gregs[REG_FP]; 200 } 201 202 address os::Solaris::ucontext_get_pc(const ucontext_t *uc) { 203 return (address) uc->uc_mcontext.gregs[REG_PC]; 204 } 205 206 // For Forte Analyzer AsyncGetCallTrace profiling support - thread 207 // is currently interrupted by SIGPROF. 208 // 209 // The difference between this and os::fetch_frame_from_context() is that 210 // here we try to skip nested signal frames. 211 // This method is also used for stack overflow signal handling. 212 ExtendedPC os::Solaris::fetch_frame_from_ucontext(Thread* thread, 213 const ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) { 214 215 assert(thread != NULL, "just checking"); 216 assert(ret_sp != NULL, "just checking"); 217 assert(ret_fp != NULL, "just checking"); 218 219 const ucontext_t *luc = os::Solaris::get_valid_uc_in_signal_handler(thread, uc); 220 return os::fetch_frame_from_context(luc, ret_sp, ret_fp); 221 } 222 223 ExtendedPC os::fetch_frame_from_context(const void* ucVoid, 224 intptr_t** ret_sp, intptr_t** ret_fp) { 225 226 ExtendedPC epc; 227 const ucontext_t *uc = (const ucontext_t*)ucVoid; 228 229 if (uc != NULL) { 230 epc = os::Solaris::ucontext_get_ExtendedPC(uc); 231 if (ret_sp) *ret_sp = os::Solaris::ucontext_get_sp(uc); 232 if (ret_fp) *ret_fp = os::Solaris::ucontext_get_fp(uc); 233 } else { 234 // construct empty ExtendedPC for return value checking 235 epc = ExtendedPC(NULL); 236 if (ret_sp) *ret_sp = (intptr_t *)NULL; 237 if (ret_fp) *ret_fp = (intptr_t *)NULL; 238 } 239 240 return epc; 241 } 242 243 frame os::fetch_frame_from_context(const void* ucVoid) { 244 intptr_t* sp; 245 intptr_t* fp; 246 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp); 247 return frame(sp, fp, epc.pc()); 248 } 249 250 frame os::fetch_frame_from_ucontext(Thread* thread, void* ucVoid) { 251 intptr_t* sp; 252 intptr_t* fp; 253 ExtendedPC epc = os::Solaris::fetch_frame_from_ucontext(thread, (ucontext_t*)ucVoid, &sp, &fp); 254 return frame(sp, fp, epc.pc()); 255 } 256 257 bool os::Solaris::get_frame_at_stack_banging_point(JavaThread* thread, ucontext_t* uc, frame* fr) { 258 address pc = (address) os::Solaris::ucontext_get_pc(uc); 259 if (Interpreter::contains(pc)) { 260 // interpreter performs stack banging after the fixed frame header has 261 // been generated while the compilers perform it before. To maintain 262 // semantic consistency between interpreted and compiled frames, the 263 // method returns the Java sender of the current frame. 264 *fr = os::fetch_frame_from_ucontext(thread, uc); 265 if (!fr->is_first_java_frame()) { 266 // get_frame_at_stack_banging_point() is only called when we 267 // have well defined stacks so java_sender() calls do not need 268 // to assert safe_for_sender() first. 269 *fr = fr->java_sender(); 270 } 271 } else { 272 // more complex code with compiled code 273 assert(!Interpreter::contains(pc), "Interpreted methods should have been handled above"); 274 CodeBlob* cb = CodeCache::find_blob(pc); 275 if (cb == NULL || !cb->is_nmethod() || cb->is_frame_complete_at(pc)) { 276 // Not sure where the pc points to, fallback to default 277 // stack overflow handling 278 return false; 279 } else { 280 // in compiled code, the stack banging is performed just after the return pc 281 // has been pushed on the stack 282 intptr_t* fp = os::Solaris::ucontext_get_fp(uc); 283 intptr_t* sp = os::Solaris::ucontext_get_sp(uc); 284 *fr = frame(sp + 1, fp, (address)*sp); 285 if (!fr->is_java_frame()) { 286 // See java_sender() comment above. 287 *fr = fr->java_sender(); 288 } 289 } 290 } 291 assert(fr->is_java_frame(), "Safety check"); 292 return true; 293 } 294 295 frame os::get_sender_for_C_frame(frame* fr) { 296 return frame(fr->sender_sp(), fr->link(), fr->sender_pc()); 297 } 298 299 extern "C" intptr_t *_get_current_sp(); // in .il file 300 301 address os::current_stack_pointer() { 302 return (address)_get_current_sp(); 303 } 304 305 extern "C" intptr_t *_get_current_fp(); // in .il file 306 307 frame os::current_frame() { 308 intptr_t* fp = _get_current_fp(); // it's inlined so want current fp 309 // fp is for os::current_frame. We want the fp for our caller. 310 frame myframe((intptr_t*)os::current_stack_pointer(), 311 (intptr_t*)fp, 312 CAST_FROM_FN_PTR(address, os::current_frame)); 313 frame caller_frame = os::get_sender_for_C_frame(&myframe); 314 315 if (os::is_first_C_frame(&caller_frame)) { 316 // stack is not walkable 317 frame ret; // This will be a null useless frame 318 return ret; 319 } else { 320 // return frame for our caller's caller 321 return os::get_sender_for_C_frame(&caller_frame); 322 } 323 } 324 325 #ifndef AMD64 326 327 // Detecting SSE support by OS 328 // From solaris_i486.s 329 extern "C" bool sse_check(); 330 extern "C" bool sse_unavailable(); 331 332 enum { SSE_UNKNOWN, SSE_NOT_SUPPORTED, SSE_SUPPORTED}; 333 static int sse_status = SSE_UNKNOWN; 334 335 336 static void check_for_sse_support() { 337 if (!VM_Version::supports_sse()) { 338 sse_status = SSE_NOT_SUPPORTED; 339 return; 340 } 341 // looking for _sse_hw in libc.so, if it does not exist or 342 // the value (int) is 0, OS has no support for SSE 343 int *sse_hwp; 344 void *h; 345 346 if ((h=dlopen("/usr/lib/libc.so", RTLD_LAZY)) == NULL) { 347 //open failed, presume no support for SSE 348 sse_status = SSE_NOT_SUPPORTED; 349 return; 350 } 351 if ((sse_hwp = (int *)dlsym(h, "_sse_hw")) == NULL) { 352 sse_status = SSE_NOT_SUPPORTED; 353 } else if (*sse_hwp == 0) { 354 sse_status = SSE_NOT_SUPPORTED; 355 } 356 dlclose(h); 357 358 if (sse_status == SSE_UNKNOWN) { 359 bool (*try_sse)() = (bool (*)())sse_check; 360 sse_status = (*try_sse)() ? SSE_SUPPORTED : SSE_NOT_SUPPORTED; 361 } 362 363 } 364 365 #endif // AMD64 366 367 bool os::supports_sse() { 368 #ifdef AMD64 369 return true; 370 #else 371 if (sse_status == SSE_UNKNOWN) 372 check_for_sse_support(); 373 return sse_status == SSE_SUPPORTED; 374 #endif // AMD64 375 } 376 377 bool os::is_allocatable(size_t bytes) { 378 #ifdef AMD64 379 return true; 380 #else 381 382 if (bytes < 2 * G) { 383 return true; 384 } 385 386 char* addr = reserve_memory(bytes, NULL); 387 388 if (addr != NULL) { 389 release_memory(addr, bytes); 390 } 391 392 return addr != NULL; 393 #endif // AMD64 394 395 } 396 397 extern "C" JNIEXPORT int 398 JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid, 399 int abort_if_unrecognized) { 400 ucontext_t* uc = (ucontext_t*) ucVoid; 401 402 #ifndef AMD64 403 if (sig == SIGILL && info->si_addr == (caddr_t)sse_check) { 404 // the SSE instruction faulted. supports_sse() need return false. 405 uc->uc_mcontext.gregs[EIP] = (greg_t)sse_unavailable; 406 return true; 407 } 408 #endif // !AMD64 409 410 Thread* t = Thread::current_or_null_safe(); 411 412 // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away 413 // (no destructors can be run) 414 os::ThreadCrashProtection::check_crash_protection(sig, t); 415 416 SignalHandlerMark shm(t); 417 418 if(sig == SIGPIPE || sig == SIGXFSZ) { 419 if (os::Solaris::chained_handler(sig, info, ucVoid)) { 420 return true; 421 } else { 422 // Ignoring SIGPIPE/SIGXFSZ - see bugs 4229104 or 6499219 423 return true; 424 } 425 } 426 427 JavaThread* thread = NULL; 428 VMThread* vmthread = NULL; 429 430 if (os::Solaris::signal_handlers_are_installed) { 431 if (t != NULL ){ 432 if(t->is_Java_thread()) { 433 thread = (JavaThread*)t; 434 } 435 else if(t->is_VM_thread()){ 436 vmthread = (VMThread *)t; 437 } 438 } 439 } 440 441 if (sig == ASYNC_SIGNAL) { 442 if(thread || vmthread){ 443 OSThread::SR_handler(t, uc); 444 return true; 445 } else if (os::Solaris::chained_handler(sig, info, ucVoid)) { 446 return true; 447 } else { 448 // If ASYNC_SIGNAL not chained, and this is a non-vm and 449 // non-java thread 450 return true; 451 } 452 } 453 454 if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) { 455 // can't decode this kind of signal 456 info = NULL; 457 } else { 458 assert(sig == info->si_signo, "bad siginfo"); 459 } 460 461 // decide if this trap can be handled by a stub 462 address stub = NULL; 463 464 address pc = NULL; 465 466 //%note os_trap_1 467 if (info != NULL && uc != NULL && thread != NULL) { 468 // factor me: getPCfromContext 469 pc = (address) uc->uc_mcontext.gregs[REG_PC]; 470 471 if (StubRoutines::is_safefetch_fault(pc)) { 472 os::Solaris::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc)); 473 return true; 474 } 475 476 // Handle ALL stack overflow variations here 477 if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) { 478 address addr = (address) info->si_addr; 479 if (thread->in_stack_yellow_reserved_zone(addr)) { 480 if (thread->thread_state() == _thread_in_Java) { 481 if (thread->in_stack_reserved_zone(addr)) { 482 frame fr; 483 if (os::Solaris::get_frame_at_stack_banging_point(thread, uc, &fr)) { 484 assert(fr.is_java_frame(), "Must be Java frame"); 485 frame activation = SharedRuntime::look_for_reserved_stack_annotated_method(thread, fr); 486 if (activation.sp() != NULL) { 487 thread->disable_stack_reserved_zone(); 488 if (activation.is_interpreted_frame()) { 489 thread->set_reserved_stack_activation((address)( 490 activation.fp() + frame::interpreter_frame_initial_sp_offset)); 491 } else { 492 thread->set_reserved_stack_activation((address)activation.unextended_sp()); 493 } 494 return true; 495 } 496 } 497 } 498 // Throw a stack overflow exception. Guard pages will be reenabled 499 // while unwinding the stack. 500 thread->disable_stack_yellow_reserved_zone(); 501 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW); 502 } else { 503 // Thread was in the vm or native code. Return and try to finish. 504 thread->disable_stack_yellow_reserved_zone(); 505 return true; 506 } 507 } else if (thread->in_stack_red_zone(addr)) { 508 // Fatal red zone violation. Disable the guard pages and fall through 509 // to handle_unexpected_exception way down below. 510 thread->disable_stack_red_zone(); 511 tty->print_raw_cr("An irrecoverable stack overflow has occurred."); 512 } 513 } 514 515 if ((sig == SIGSEGV) && VM_Version::is_cpuinfo_segv_addr(pc)) { 516 // Verify that OS save/restore AVX registers. 517 stub = VM_Version::cpuinfo_cont_addr(); 518 } 519 520 if (thread->thread_state() == _thread_in_vm) { 521 if (sig == SIGBUS && info->si_code == BUS_OBJERR && thread->doing_unsafe_access()) { 522 address next_pc = Assembler::locate_next_instruction(pc); 523 stub = SharedRuntime::handle_unsafe_access(thread, next_pc); 524 } 525 } 526 527 if (thread->thread_state() == _thread_in_Java) { 528 // Support Safepoint Polling 529 if ( sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) { 530 stub = SharedRuntime::get_poll_stub(pc); 531 } 532 else if (sig == SIGBUS && info->si_code == BUS_OBJERR) { 533 // BugId 4454115: A read from a MappedByteBuffer can fault 534 // here if the underlying file has been truncated. 535 // Do not crash the VM in such a case. 536 CodeBlob* cb = CodeCache::find_blob_unsafe(pc); 537 if (cb != NULL) { 538 CompiledMethod* nm = cb->as_compiled_method_or_null(); 539 if (nm != NULL && nm->has_unsafe_access()) { 540 address next_pc = Assembler::locate_next_instruction(pc); 541 stub = SharedRuntime::handle_unsafe_access(thread, next_pc); 542 } 543 } 544 } 545 else 546 if (sig == SIGFPE && info->si_code == FPE_INTDIV) { 547 // integer divide by zero 548 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); 549 } 550 #ifndef AMD64 551 else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) { 552 // floating-point divide by zero 553 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); 554 } 555 else if (sig == SIGFPE && info->si_code == FPE_FLTINV) { 556 // The encoding of D2I in i486.ad can cause an exception prior 557 // to the fist instruction if there was an invalid operation 558 // pending. We want to dismiss that exception. From the win_32 559 // side it also seems that if it really was the fist causing 560 // the exception that we do the d2i by hand with different 561 // rounding. Seems kind of weird. QQQ TODO 562 // Note that we take the exception at the NEXT floating point instruction. 563 if (pc[0] == 0xDB) { 564 assert(pc[0] == 0xDB, "not a FIST opcode"); 565 assert(pc[1] == 0x14, "not a FIST opcode"); 566 assert(pc[2] == 0x24, "not a FIST opcode"); 567 return true; 568 } else { 569 assert(pc[-3] == 0xDB, "not an flt invalid opcode"); 570 assert(pc[-2] == 0x14, "not an flt invalid opcode"); 571 assert(pc[-1] == 0x24, "not an flt invalid opcode"); 572 } 573 } 574 else if (sig == SIGFPE ) { 575 tty->print_cr("caught SIGFPE, info 0x%x.", info->si_code); 576 } 577 #endif // !AMD64 578 579 // QQQ It doesn't seem that we need to do this on x86 because we should be able 580 // to return properly from the handler without this extra stuff on the back side. 581 582 else if (sig == SIGSEGV && info->si_code > 0 && !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) { 583 // Determination of interpreter/vtable stub/compiled code null exception 584 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); 585 } 586 } 587 588 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in 589 // and the heap gets shrunk before the field access. 590 if ((sig == SIGSEGV) || (sig == SIGBUS)) { 591 address addr = JNI_FastGetField::find_slowcase_pc(pc); 592 if (addr != (address)-1) { 593 stub = addr; 594 } 595 } 596 597 // Check to see if we caught the safepoint code in the 598 // process of write protecting the memory serialization page. 599 // It write enables the page immediately after protecting it 600 // so we can just return to retry the write. 601 if ((sig == SIGSEGV) && 602 os::is_memory_serialize_page(thread, (address)info->si_addr)) { 603 // Block current thread until the memory serialize page permission restored. 604 os::block_on_serialize_page_trap(); 605 return true; 606 } 607 } 608 609 // Execution protection violation 610 // 611 // Preventative code for future versions of Solaris which may 612 // enable execution protection when running the 32-bit VM on AMD64. 613 // 614 // This should be kept as the last step in the triage. We don't 615 // have a dedicated trap number for a no-execute fault, so be 616 // conservative and allow other handlers the first shot. 617 // 618 // Note: We don't test that info->si_code == SEGV_ACCERR here. 619 // this si_code is so generic that it is almost meaningless; and 620 // the si_code for this condition may change in the future. 621 // Furthermore, a false-positive should be harmless. 622 if (UnguardOnExecutionViolation > 0 && 623 (sig == SIGSEGV || sig == SIGBUS) && 624 uc->uc_mcontext.gregs[TRAPNO] == T_PGFLT) { // page fault 625 int page_size = os::vm_page_size(); 626 address addr = (address) info->si_addr; 627 address pc = (address) uc->uc_mcontext.gregs[REG_PC]; 628 // Make sure the pc and the faulting address are sane. 629 // 630 // If an instruction spans a page boundary, and the page containing 631 // the beginning of the instruction is executable but the following 632 // page is not, the pc and the faulting address might be slightly 633 // different - we still want to unguard the 2nd page in this case. 634 // 635 // 15 bytes seems to be a (very) safe value for max instruction size. 636 bool pc_is_near_addr = 637 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15); 638 bool instr_spans_page_boundary = 639 (align_down((intptr_t) pc ^ (intptr_t) addr, 640 (intptr_t) page_size) > 0); 641 642 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) { 643 static volatile address last_addr = 644 (address) os::non_memory_address_word(); 645 646 // In conservative mode, don't unguard unless the address is in the VM 647 if (addr != last_addr && 648 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) { 649 650 // Make memory rwx and retry 651 address page_start = align_down(addr, page_size); 652 bool res = os::protect_memory((char*) page_start, page_size, 653 os::MEM_PROT_RWX); 654 655 log_debug(os)("Execution protection violation " 656 "at " INTPTR_FORMAT 657 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", p2i(addr), 658 p2i(page_start), (res ? "success" : "failed"), errno); 659 stub = pc; 660 661 // Set last_addr so if we fault again at the same address, we don't end 662 // up in an endless loop. 663 // 664 // There are two potential complications here. Two threads trapping at 665 // the same address at the same time could cause one of the threads to 666 // think it already unguarded, and abort the VM. Likely very rare. 667 // 668 // The other race involves two threads alternately trapping at 669 // different addresses and failing to unguard the page, resulting in 670 // an endless loop. This condition is probably even more unlikely than 671 // the first. 672 // 673 // Although both cases could be avoided by using locks or thread local 674 // last_addr, these solutions are unnecessary complication: this 675 // handler is a best-effort safety net, not a complete solution. It is 676 // disabled by default and should only be used as a workaround in case 677 // we missed any no-execute-unsafe VM code. 678 679 last_addr = addr; 680 } 681 } 682 } 683 684 if (stub != NULL) { 685 // save all thread context in case we need to restore it 686 687 if (thread != NULL) thread->set_saved_exception_pc(pc); 688 // 12/02/99: On Sparc it appears that the full context is also saved 689 // but as yet, no one looks at or restores that saved context 690 os::Solaris::ucontext_set_pc(uc, stub); 691 return true; 692 } 693 694 // signal-chaining 695 if (os::Solaris::chained_handler(sig, info, ucVoid)) { 696 return true; 697 } 698 699 #ifndef AMD64 700 // Workaround (bug 4900493) for Solaris kernel bug 4966651. 701 // Handle an undefined selector caused by an attempt to assign 702 // fs in libthread getipriptr(). With the current libthread design every 512 703 // thread creations the LDT for a private thread data structure is extended 704 // and thre is a hazard that and another thread attempting a thread creation 705 // will use a stale LDTR that doesn't reflect the structure's growth, 706 // causing a GP fault. 707 // Enforce the probable limit of passes through here to guard against an 708 // infinite loop if some other move to fs caused the GP fault. Note that 709 // this loop counter is ultimately a heuristic as it is possible for 710 // more than one thread to generate this fault at a time in an MP system. 711 // In the case of the loop count being exceeded or if the poll fails 712 // just fall through to a fatal error. 713 // If there is some other source of T_GPFLT traps and the text at EIP is 714 // unreadable this code will loop infinitely until the stack is exausted. 715 // The key to diagnosis in this case is to look for the bottom signal handler 716 // frame. 717 718 if(! IgnoreLibthreadGPFault) { 719 if (sig == SIGSEGV && uc->uc_mcontext.gregs[TRAPNO] == T_GPFLT) { 720 const unsigned char *p = 721 (unsigned const char *) uc->uc_mcontext.gregs[EIP]; 722 723 // Expected instruction? 724 725 if(p[0] == movlfs[0] && p[1] == movlfs[1]) { 726 727 Atomic::inc(&ldtr_refresh); 728 729 // Infinite loop? 730 731 if(ldtr_refresh < ((2 << 16) / PAGESIZE)) { 732 733 // No, force scheduling to get a fresh view of the LDTR 734 735 if(poll(NULL, 0, 10) == 0) { 736 737 // Retry the move 738 739 return false; 740 } 741 } 742 } 743 } 744 } 745 #endif // !AMD64 746 747 if (!abort_if_unrecognized) { 748 // caller wants another chance, so give it to him 749 return false; 750 } 751 752 if (!os::Solaris::libjsig_is_loaded) { 753 struct sigaction oldAct; 754 sigaction(sig, (struct sigaction *)0, &oldAct); 755 if (oldAct.sa_sigaction != signalHandler) { 756 void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) 757 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); 758 warning("Unexpected Signal %d occurred under user-defined signal handler %#lx", sig, (long)sighand); 759 } 760 } 761 762 if (pc == NULL && uc != NULL) { 763 pc = (address) uc->uc_mcontext.gregs[REG_PC]; 764 } 765 766 // unmask current signal 767 sigset_t newset; 768 sigemptyset(&newset); 769 sigaddset(&newset, sig); 770 sigprocmask(SIG_UNBLOCK, &newset, NULL); 771 772 // Determine which sort of error to throw. Out of swap may signal 773 // on the thread stack, which could get a mapping error when touched. 774 address addr = (address) info->si_addr; 775 if (sig == SIGBUS && info->si_code == BUS_OBJERR && info->si_errno == ENOMEM) { 776 vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "Out of swap space to map in thread stack."); 777 } 778 779 VMError::report_and_die(t, sig, pc, info, ucVoid); 780 781 ShouldNotReachHere(); 782 return false; 783 } 784 785 void os::print_context(outputStream *st, const void *context) { 786 if (context == NULL) return; 787 788 const ucontext_t *uc = (const ucontext_t*)context; 789 st->print_cr("Registers:"); 790 #ifdef AMD64 791 st->print( "RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]); 792 st->print(", RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]); 793 st->print(", RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]); 794 st->print(", RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]); 795 st->cr(); 796 st->print( "RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]); 797 st->print(", RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]); 798 st->print(", RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]); 799 st->print(", RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]); 800 st->cr(); 801 st->print( "R8 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]); 802 st->print(", R9 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]); 803 st->print(", R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]); 804 st->print(", R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]); 805 st->cr(); 806 st->print( "R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]); 807 st->print(", R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]); 808 st->print(", R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]); 809 st->print(", R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]); 810 st->cr(); 811 st->print( "RIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RIP]); 812 st->print(", RFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RFL]); 813 #else 814 st->print( "EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EAX]); 815 st->print(", EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBX]); 816 st->print(", ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ECX]); 817 st->print(", EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDX]); 818 st->cr(); 819 st->print( "ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[UESP]); 820 st->print(", EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EBP]); 821 st->print(", ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[ESI]); 822 st->print(", EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EDI]); 823 st->cr(); 824 st->print( "EIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EIP]); 825 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[EFL]); 826 #endif // AMD64 827 st->cr(); 828 st->cr(); 829 830 intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc); 831 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp); 832 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t)); 833 st->cr(); 834 835 // Note: it may be unsafe to inspect memory near pc. For example, pc may 836 // point to garbage if entry point in an nmethod is corrupted. Leave 837 // this at the end, and hope for the best. 838 ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc); 839 address pc = epc.pc(); 840 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc); 841 print_hex_dump(st, pc - 32, pc + 32, sizeof(char)); 842 } 843 844 void os::print_register_info(outputStream *st, const void *context) { 845 if (context == NULL) return; 846 847 const ucontext_t *uc = (const ucontext_t*)context; 848 849 st->print_cr("Register to memory mapping:"); 850 st->cr(); 851 852 // this is horrendously verbose but the layout of the registers in the 853 // context does not match how we defined our abstract Register set, so 854 // we can't just iterate through the gregs area 855 856 // this is only for the "general purpose" registers 857 858 #ifdef AMD64 859 st->print("RAX="); print_location(st, uc->uc_mcontext.gregs[REG_RAX]); 860 st->print("RBX="); print_location(st, uc->uc_mcontext.gregs[REG_RBX]); 861 st->print("RCX="); print_location(st, uc->uc_mcontext.gregs[REG_RCX]); 862 st->print("RDX="); print_location(st, uc->uc_mcontext.gregs[REG_RDX]); 863 st->print("RSP="); print_location(st, uc->uc_mcontext.gregs[REG_RSP]); 864 st->print("RBP="); print_location(st, uc->uc_mcontext.gregs[REG_RBP]); 865 st->print("RSI="); print_location(st, uc->uc_mcontext.gregs[REG_RSI]); 866 st->print("RDI="); print_location(st, uc->uc_mcontext.gregs[REG_RDI]); 867 st->print("R8 ="); print_location(st, uc->uc_mcontext.gregs[REG_R8]); 868 st->print("R9 ="); print_location(st, uc->uc_mcontext.gregs[REG_R9]); 869 st->print("R10="); print_location(st, uc->uc_mcontext.gregs[REG_R10]); 870 st->print("R11="); print_location(st, uc->uc_mcontext.gregs[REG_R11]); 871 st->print("R12="); print_location(st, uc->uc_mcontext.gregs[REG_R12]); 872 st->print("R13="); print_location(st, uc->uc_mcontext.gregs[REG_R13]); 873 st->print("R14="); print_location(st, uc->uc_mcontext.gregs[REG_R14]); 874 st->print("R15="); print_location(st, uc->uc_mcontext.gregs[REG_R15]); 875 #else 876 st->print("EAX="); print_location(st, uc->uc_mcontext.gregs[EAX]); 877 st->print("EBX="); print_location(st, uc->uc_mcontext.gregs[EBX]); 878 st->print("ECX="); print_location(st, uc->uc_mcontext.gregs[ECX]); 879 st->print("EDX="); print_location(st, uc->uc_mcontext.gregs[EDX]); 880 st->print("ESP="); print_location(st, uc->uc_mcontext.gregs[UESP]); 881 st->print("EBP="); print_location(st, uc->uc_mcontext.gregs[EBP]); 882 st->print("ESI="); print_location(st, uc->uc_mcontext.gregs[ESI]); 883 st->print("EDI="); print_location(st, uc->uc_mcontext.gregs[EDI]); 884 #endif 885 886 st->cr(); 887 } 888 889 890 #ifdef AMD64 891 void os::Solaris::init_thread_fpu_state(void) { 892 // Nothing to do 893 } 894 #else 895 // From solaris_i486.s 896 extern "C" void fixcw(); 897 898 void os::Solaris::init_thread_fpu_state(void) { 899 // Set fpu to 53 bit precision. This happens too early to use a stub. 900 fixcw(); 901 } 902 903 // These routines are the initial value of atomic_xchg_entry(), 904 // atomic_cmpxchg_entry(), atomic_inc_entry() and fence_entry() 905 // until initialization is complete. 906 // TODO - replace with .il implementation when compiler supports it. 907 908 typedef jint xchg_func_t (jint, volatile jint*); 909 typedef jint cmpxchg_func_t (jint, volatile jint*, jint); 910 typedef jlong cmpxchg_long_func_t(jlong, volatile jlong*, jlong); 911 typedef jint add_func_t (jint, volatile jint*); 912 913 jint os::atomic_xchg_bootstrap(jint exchange_value, volatile jint* dest) { 914 // try to use the stub: 915 xchg_func_t* func = CAST_TO_FN_PTR(xchg_func_t*, StubRoutines::atomic_xchg_entry()); 916 917 if (func != NULL) { 918 os::atomic_xchg_func = func; 919 return (*func)(exchange_value, dest); 920 } 921 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 922 923 jint old_value = *dest; 924 *dest = exchange_value; 925 return old_value; 926 } 927 928 jint os::atomic_cmpxchg_bootstrap(jint exchange_value, volatile jint* dest, jint compare_value) { 929 // try to use the stub: 930 cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry()); 931 932 if (func != NULL) { 933 os::atomic_cmpxchg_func = func; 934 return (*func)(exchange_value, dest, compare_value); 935 } 936 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 937 938 jint old_value = *dest; 939 if (old_value == compare_value) 940 *dest = exchange_value; 941 return old_value; 942 } 943 944 jlong os::atomic_cmpxchg_long_bootstrap(jlong exchange_value, volatile jlong* dest, jlong compare_value) { 945 // try to use the stub: 946 cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry()); 947 948 if (func != NULL) { 949 os::atomic_cmpxchg_long_func = func; 950 return (*func)(exchange_value, dest, compare_value); 951 } 952 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 953 954 jlong old_value = *dest; 955 if (old_value == compare_value) 956 *dest = exchange_value; 957 return old_value; 958 } 959 960 jint os::atomic_add_bootstrap(jint add_value, volatile jint* dest) { 961 // try to use the stub: 962 add_func_t* func = CAST_TO_FN_PTR(add_func_t*, StubRoutines::atomic_add_entry()); 963 964 if (func != NULL) { 965 os::atomic_add_func = func; 966 return (*func)(add_value, dest); 967 } 968 assert(Threads::number_of_threads() == 0, "for bootstrap only"); 969 970 return (*dest) += add_value; 971 } 972 973 xchg_func_t* os::atomic_xchg_func = os::atomic_xchg_bootstrap; 974 cmpxchg_func_t* os::atomic_cmpxchg_func = os::atomic_cmpxchg_bootstrap; 975 cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap; 976 add_func_t* os::atomic_add_func = os::atomic_add_bootstrap; 977 978 extern "C" void _solaris_raw_setup_fpu(address ptr); 979 void os::setup_fpu() { 980 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std(); 981 _solaris_raw_setup_fpu(fpu_cntrl); 982 } 983 #endif // AMD64 984 985 #ifndef PRODUCT 986 void os::verify_stack_alignment() { 987 #ifdef AMD64 988 assert(((intptr_t)os::current_stack_pointer() & (StackAlignmentInBytes-1)) == 0, "incorrect stack alignment"); 989 #endif 990 } 991 #endif 992 993 int os::extra_bang_size_in_bytes() { 994 // JDK-8050147 requires the full cache line bang for x86. 995 return VM_Version::L1_line_size(); 996 }